Table 1 Demographic characteristics of included studies
Author (Year) | Country | Study design | Sample size | N mother with (d3) deficiency | N child with DC | Mean Age of pregnant mothers | Sex child (Male) | prenatal (D3) deficiency definition (nmol/L) | Childs age group (years) | Maternal educational level < 13 grade | Gestational Age (weeks) | Quality of studies |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
RJ Schroth(2014) [5] | USA | prospective cohort | 207 | 65 | 30 | 19 | 75 | ≤ 35 | 4 to 6 | 63 | 12 to 18 | Fair |
K Tanaka(2015) [4] | Japanese | prospective cohort | 1210 | 605 | 154 | 31.6 | 571 | ≤ 35 | 2 to 4 | 82 | 12 to 18 | Good |
Canada | prospective cohort | 175 | 85 | 26 | 23.05 | 84 | ≤ 50 | 4 to 6 | NA | 6 to 38 | Fair | |
S Korun(2017) | Turkey | prospective cohort | 50 | 31 | 28 | 20.1 | 23 | ≤ 35 | 4 to 6 | 28 | 24 to 36 | Poor |
R Singleton(2019) [33] | Canada | prospective cohort | 78 | 23 | 13 | 26.1 | 41 | ≤ 35 | 2 to 4 | NA | 16 to 38 | Poor |
MJ Silva(2019) [34] | Australia | prospective cohort | 345 | NA | 111 | NA | 163 | ≤ 35 | 6 to 8 | 699 | 24 to 36 | Good |
RJ Schroth(2020) [28] | Canada | prospective cohort | 283 | 126 | 26 | 29.5 | 154 | ≤ 35 | 2 to 4 | 76 | 6 to 38 | Good |
C Suárez-Calleja(2021) [48] | Spain | prospective cohort | 178 | 110 | 38 | 25.7 | 87 | ≤ 35 | 4 to 6 | NA | 18 to 24 | Fair |
CLA Navarro(2021) [36] | Netherland | Cross -sectional | 5257 | *1218 *1402 | *589 *457 | 30.6 | 2634 | ≤ 35 ≤ 50 | 4 to 6 | 1748 | 18 to 38 | Good |
D Olczak-Kowalczyk(2021) [35] | Poland | prospective cohort | 1638 | 734 | 328 | 25.9 | NA | ≤ 50 | 4 to 6 | NA | 24 to 36 | Good |
DM Beckett(2022) [38] | New Zealand | prospective cohort | 78 | 12 | 24 | 25.9 | NA | ≤ 50 | 4 to 6 | NA | 24 to 36 | Poor |
RJ Singleton(2022) | USA | Retrospective cohorts | 1522 | 438 | NA | 28.2 | 94 | ≤ 50 | 4 to 6 | NA | 24 to 36 | Fair |